Digg today announced it is expanding its recently-launched Digg Deeper service, which shows you what interesting links your friends are sharing on Twitter. The new feature has been integrated into its Digg Reader app as well as its iOS app, and is also getting a Daily Digest email option.

Digg Reader now shows you the most-shared stories, videos and links from your Twitter connections. If you’ve always wanted a way to keep up with both RSS and Twitter, this might be it.

Digg for iOS has been updated to version 5.4.1 over on Apple’s App Store to integrate Digg Deeper. Although mobile notifications for trending stories were available at launch, you can now see which of your friends shared each story and read their tweets about it.

The Daily Digest email option (you have to turn it on in Settings) is an alternative to the optional real-time email alerts that were also available at launch. It pulls all your Digg Deeper links into a single place and delivers them just once a day to your inbox.

Today’s expansion suggests Digg is so far pleased with its Deeper experiment. While Digg is unlikely to ever return to its peak height of popularity, the parent company Betaworks is doing a great job of positioning Digg as an umbrella of multiple news curation services: an editorial team manning the main Digg site, an RSS service, and now a social-powered offering. Now it’s just trying to tie them all together.

The company still hasn’t revealed when it plans to add additional social networks to Digg Deeper, or when the Android app will get the same treatment as iOS. We have contacted Betaworks and will update this post if we hear back with more information.

See alsoDigg launches Reader extension for Chrome, adds unread mode to Android app and Kevin Rose wants to launch another startup, wishes he had stayed CEO of Digg

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